FRACTURE MECHANICS OF PIEZOELECTRIC/FERROELECTRIC MATERIALS
作者单位：State Key Laboratory for Strength and Vibration of Mechanical StructuresSchool of Aerospace Xi’an Jiaotong University
会议名称：《2016年全国压电和声波理论及器件应用研讨会》
会议日期：2016年
学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学]
基 金：supported by the National Natural Science Foundation of China (Nos. 11321062, 11472205) the Fundamental Research Funds for the Central Universities in China Natural Science Basic Research Plan in Shaanxi Province of China (Program No. 2014K10-16, 2014XT-08)
关 键 词：Piezoelectric ferroelectrics domain switching crack fracture
摘 要：Background, Motivation and Objective Piezoelectric/Ferroelectric ceramics are brittle and susceptible to cracking at all scales ranging from electric domain to devices, due to the inhomogeneous electro-mechanical fields induced by domain switching near the crack tip. Therefore, capturing nonlinear constitutive behavior based on micromechanical modeling of domain switching is inevitable to analyze fracture behavior in ferroelectric materials. This paper is devoted to report on the fracture behavior and domain structure evolution induced by the applied electric fields which are considered to be perpendicular to the crack surfaces. The electromechanical fracture behavior of ferroelectrics is evaluated by the concept of configurational forces. Besides, the birefringence experiments are conducted to observe the variation of spontaneous polarization and electrical creep and domain switching emission. Also, two-dimensional phase field simulations are carried out to capture electrical creep and domain switching emission from the crack tip of a stationary inclined crack embedded in ferroelectrics. Statement of Contribution/Methods The microstructure of domain evolution is simulated near the crack tip. The electromechanical fracture behavior of ferroelectrics is evaluated by the concept of configurational forces which interpreted as the crack driving force. The spatial and temporal evolution of domain switching near the tip of an inclined crack is observed in ferroelectrics by a standard birefringence system. Moreover, the phase field modeling is developed to simulate polarization distribution and domain switching near the crack tip where the time-dependent Ginzburg–Landau equation is used to describe the change of polarization. Results The configurational force with respect to the applied electric field shows a butterfly loop for the initially unpoled ferroelectric status while only a half butterfly loop for the initially poled case is obtained. The birefringence results sho